function changeVolumeOnVolumeChange()
{
    frmButton = document.getElementById( 'ArchiveMovieButton' );
    frmSelect = document.getElementById( 'ArchiveMovieVolumesList' );

    frmButton.disabled = ( frmSelect.options[ frmSelect.selectedIndex ].value == 0 );
}

addListener( window, 'load', function() {
    if ( item = document.getElementById( 'ArchiveMovieVolumesList' ) )
        addListener( item, 'change', changeVolumeOnVolumeChange );
});